:root {
  color-scheme: dark;
  --color-bg-app: #090f1d;
  --color-surface: #121a2c;
  --color-surface-elevated: #1a253b;
  --color-border: #314364;
  --color-text-primary: #e7edf8;
  --color-text-secondary: #a9b8d2;
  --color-accent: #6366f1;
  --color-accent-strong: #4f46e5;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 22px;
  font-family: 'Plus Jakarta Sans', 'Inter', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', 'Segoe UI', -apple-system, BlinkMacSystemFont, sans-serif;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  color: var(--color-text-primary);
  background:
    radial-gradient(900px 420px at 12% -10%, rgba(99, 102, 241, 0.22), transparent 62%),
    radial-gradient(840px 420px at 110% 5%, rgba(14, 165, 233, 0.16), transparent 65%),
    var(--color-bg-app);
}

.bg-grid {
  position: fixed;
  inset: 0;
  background-image:
    linear-gradient(rgba(127, 146, 179, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(127, 146, 179, 0.05) 1px, transparent 1px);
  background-size: 28px 28px;
  mask-image: radial-gradient(circle at 50% 20%, black 35%, transparent 90%);
  pointer-events: none;
  z-index: -1;
}

.topbar {
  max-width: 980px;
  margin: 0 auto;
  padding: 20px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  position: sticky;
  top: 0;
  z-index: 20;
  backdrop-filter: blur(10px);
}

.brand {
  color: var(--color-text-primary);
  text-decoration: none;
  font-size: 1.05rem;
  font-weight: 700;
  display: inline-flex;
  align-items: center;
  gap: 10px;
}

.brand img {
  width: 30px;
  height: 30px;
  border-radius: 8px;
  box-shadow: 0 4px 12px rgba(2, 6, 23, 0.4);
  animation: floatY 3s ease-in-out infinite;
}

.nav {
  display: flex;
  gap: 8px;
}

.nav a {
  color: var(--color-text-secondary);
  text-decoration: none;
  padding: 8px 12px;
  border-radius: 999px;
}

.nav a.active,
.nav a:hover {
  color: var(--color-text-primary);
  background: rgba(99, 102, 241, 0.18);
}

.main {
  max-width: 980px;
  margin: 0 auto;
  padding: 16px 20px 42px;
}

.hero {
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  background: rgba(18, 26, 44, 0.85);
  padding: 28px;
  animation: fadeUp 0.7s ease both;
}

.eyebrow {
  margin: 0;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: #9bb0ff;
  font-size: 0.78rem;
  font-weight: 700;
}

.hero h1 {
  margin: 8px 0 10px;
  font-size: clamp(1.8rem, 3vw, 2.5rem);
}

.hero p {
  margin: 0;
  color: var(--color-text-secondary);
}

.steps {
  margin-top: 20px;
  display: grid;
  gap: 12px;
}

.step-card {
  display: grid;
  grid-template-columns: 54px 1fr auto;
  gap: 14px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 16px;
  background: color-mix(in srgb, var(--color-surface-elevated) 84%, transparent);
  align-items: center;
  transition: transform 0.24s ease, border-color 0.24s ease, box-shadow 0.24s ease;
}

.step-card:hover {
  transform: translateY(-3px);
  border-color: #46618e;
  box-shadow: 0 10px 24px rgba(2, 6, 23, 0.32);
}

.step-index {
  width: 46px;
  height: 46px;
  border-radius: 12px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: rgba(99, 102, 241, 0.18);
  color: #d5ddff;
  font-weight: 700;
}

.step-card h2 {
  margin: 0 0 4px;
  font-size: 1.06rem;
}

.step-card p {
  margin: 0;
  color: var(--color-text-secondary);
  line-height: 1.7;
}

.link-btn {
  text-decoration: none;
  border-radius: var(--radius-md);
  padding: 10px 14px;
  color: #fff;
  background: linear-gradient(120deg, var(--color-accent), var(--color-accent-strong));
  font-weight: 600;
  white-space: nowrap;
}

.cta {
  margin-top: 20px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: 20px;
  background: linear-gradient(130deg, rgba(25, 38, 65, 0.9), rgba(16, 26, 44, 0.9));
}

.cta h2 {
  margin: 0;
  font-size: 1.3rem;
}

.cta p {
  margin: 8px 0 14px;
  color: var(--color-text-secondary);
}

.reveal {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.55s ease, transform 0.55s ease;
}

.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}

@keyframes floatY {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-4px); }
}

@keyframes fadeUp {
  from {
    opacity: 0;
    transform: translateY(16px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@media (max-width: 860px) {
  .step-card {
    grid-template-columns: 46px 1fr;
  }

  .step-card .link-btn {
    grid-column: 1 / -1;
    justify-self: start;
  }
}

@media (max-width: 640px) {
  .topbar {
    flex-direction: column;
    align-items: flex-start;
    gap: 12px;
  }

  .nav {
    flex-wrap: wrap;
  }
}